Chemical tablet dispensing device for wells

ABSTRACT

A chemical tablet dispensing device for wells is disclosed herein and generally comprises a housing positioned over the well. A sealed tablet hopper is provided at the upper end of the housing for supplying chemical tablets to a metering device which is detachably mounted on the lower end of the hopper. The metering device includes a rotatable metering plate adapted to supply a chemical tablet to a communicating tube after predetermined periods of pump operation. Means is also provided to cause the metering device to supply the tablets to the well at predetermined times even if the pump is not being used. The communicating tube deposits the chemical tablet into the well to treat the water therein. Electrical control means is provided for controlling the rotation of the metering plate so that the metering plate is rotated at a predetermined rate during actual pump operation. Means is also provided for preventing moist air from the well from damaging the componenets of the device.

United States Patent [191 Handeland 1 CHEMICAL TABLET DISPENSING DEVICEFOR WELLS [75] Inventor: George A. llandeland, Ringsted,

Iowa

[73] Assignee: Safe Well Manufacturing Company, Albert City, Iowa 221Filed: Jan. 31, 1972- 211 App1.No.: 221,920

[52] US. Cl...'.' 221/265, 221/15 [51] Int. Cl. B65g 59/06 [58] Field ofSearch 221/12, 13,203,

[56] References Cited UNITED STATES PATENTS 3,022,247 2/1962 Selby etal. 210/170 X 3,253,738 5/1966 Bromley 221/265 X 1,523,118 1/1925 Green..l 210/59 FOREIGN PATENTS OR APPLICATIONS 1,086,632 8/1954 France221/15 1- .Ian. 15, 1974 Primary Examiner-Stanley H. TollbergAttorney-Zarley, McKee & Thomte [5 7] ABSTRACT A chemical tabletdispensing device for wells is disclosed herein and generally comprisesa housing positioned over the well. A sealed tablet hopper is providedat the upper end of the housing for supplying chemical tablets to ametering device which is detachably mounted .on the lower end of thehopper. The metering device includes a rotatable metering plate adaptedto supply a chemical tablet to a communicating tube after predeterminedperiods of pump operation. Means is also provided to cause the meteringdevice to supply the tablets to the well at predetermined times even ifthe pump is not being used. The communicating tube deposits the chemicaltablet into the well to treat the water therein. Electrical controlmeans is provided for controlling the rotation of the metering plate sothat the metering plate is rotated at a predetermined rate during actualpump operation. Means is also provided for preventing moist air from thewell from damaging the componenets of the device.

12 Claims, 11 Drawing Figures PATENTEDJAN 1 m 3'. 785525 I I SHEEIIUFBPATENIED 3,785,525

saw 2 OF 3 Nov.

CHEMICAL TABLET DISPENSING DEVICE FOR WELLS Many homes are not connectedto water supply lines but are connected to water wells including pumpmeans for furnishing water under pressure to the home. It is frequentlydesirable or necessary to treat the well water to purify the same. Theproblems ordinarily associated with the treatment of the water are: (l)expense; (2) convenience; and (3) accuracy.

Therefore, it is a principal object of this-invention to provide achemical tablet dispensing device for wells.

A furtherobject of this invention is to provide a chemical tabletdispensing device for wells which is inexpensive to manufacture andinexpensive to operate.

A further object of this invention is to provide a chemical tabletdispensing device for wells which is convenient.

A further object of this invention is to provide a chemical tabletdispensing device for wells which accurately meters the proper amount ofchemical tablets into the well.

A further object of this invention is to provide a chemical tabletdispensing device for wells which meters chemical tablets into the wellproportionately to the amount of water being pumped from the well.

A further object of this invention is to provide a chemical tabletdispensing device for wells including means to prevent moisture fromaccumulating therein.

A further object of this invention is to provide a chemical tabletdispensing device 'for wells including means for preventing overheatingof the metering deyice motor and gear box.

A further object of this invention is to provide a chemical tabletdispensing device for wells including a metering device having a clutchmeans thereon.

A further object of this invention is to provide a chemical tabletdispensing device for wells including a metering device having meansthereonfor preventing the tablets from becoming stuck therein.

A further object of this invention is to provide a chemical tabletdispensing device for wells including a removable metering device.

A further object of this invention is to provide a chemical tabletdispensing device for wells which is durable in use.

These and other objects will be apparent to those skilled in the art.

This invention consists in the construction, arrangements andcombination ofthe various parts of the device, whereby the objectscontemplated are attained as hereinafter more fully set forth,specifically pointed out in the claims, and illustrated in theaccompanying drawings, in which:

FIG. 1 is a side elevational view of the device of this inventionmounted over a well with portions thereof cut away to more fullyillustrate .the invention;

FIG. 2 is a partial sectional viewof the metering device;

FIG. 3 is an enlarged sectional view seen along lines 3-3 of FIG. 2: i

FIG. 4 is a sectional view seen along lines 44 of FIG. 2:

FIG. 5 is an enlarged sectional view seen along lines 5-5 with portionsthereof cut away to more fully illustrate the invention:

FIG. 6 is a sectional view seen along lines 6-6 of FIG. 5:

FIG. 7 is a view similar to FIG. 1;

FIG. 8 is a schematic illustration of the electrical circuitry of thedevice;

FIG. 9 is a partial side view of a modified form of the invention withportionsthereof cut away to more fully illustrate the invention;

FIG. 10 is an enlarged sectional view seen along lines 10-l0 of FIG. 9;and

FIG. 11 is an enlarged sectional view seen along lines 11-11 of FIG. 9.

The numeral 10 designates a water well having a conventional water pumpmeans 12 associated therewith for pumping water from the well asdesired.Pump means 12 is operated by an electrical pump motor 14 which ispreferably controlled by conventional automatic control means includinga pressure tank 15. In FIGS. 1-7, the numeral 16 refers to the chemicaltablet dispensing device of this invention.

Device 16 includes a housing positioned over the well as illustrated inFIGS. 1 and 7. Housing 18 should be air tight to prevent moist air fromcollecting therein. A tablet hopper 20 is positioned in the upper end ofthe housing 18 and chemical tablets or pellets 22, such as chlorine, aredeposited in the hopper 20 through the sealed cap 24. y

The lower end of hopper 20 terminates in a cylindrical collar portion 26having an open lower end. The metering device 28 of this invention isremovably mounted on collar portion 26 by means of connecting element30. Connecting element 30 is best illustrated in FIG. 3 and includes acylinder 32 welded to collar portion 26. Cylinder 32 has a plurality ofspaced apart openings 34 formed therein adapted to receive pin 36 topermit the selective tensioning of spring 38 which yieldably urgesplunger 40 through opening 42 in collar portion 26 into engagement withrecess 44 to suspend the metering device 28 from the hopper 20. Themetering device 28 is easily removed from the hopper 20 by simplyremoving pin 36 so that plunger 40 can be moved out of engagement withrecess 44.

Metering device 28 is comprised of base plate 46 and a cylindricalcollar 48 secured thereto and extending upwardly therefrom into collarportion 26. Bond 49 limits the upward movement of device 28 with respectto collar portion 26. A secondary base plate 50 is suspended below baseplate 46 by bolts 52. Motor 108 and gear box 56 are supported by baseplate 50 as illustrated in FIG. 2. Gear box 56 is spaced below baseplate 50 to permit air to surround the gearbox to keep it cool duringoperation thereof. Output shaft 58 extends upwardly from gear box 56through plate 50 as shown' in FIG. 5. A clutch element 60 rotatablyembraces shaft 56 and generally comprises a collar 62 rigidly secured toclutchelement 60 by means of set screw 64. Clutch element 60 and collar62 are releasably secured to shaft 58 by means of ball and springassembly 66. Ball 68 of assembly 66 is normally urged into engagementwith the V-shaped notch 70 formed in shaft 58. Clutch element 60 isprovided with teeth 72 at its upper end which loosely mesh with teeth 74of clutch element 76. Clutch element 76 is secured to shaft 78 by pin80. Shaft 78 rotatably extends upwardly through plate 46 and throughmetering plate 82. Shaft 78 has a pair of spaced apart baffles 84 and 86secured thereto which have a diameter substantially identical to the topopening 88 in element 48. A cone 90 is rigidly secured to shaft 78 andhas a drive-shear pin 92 extending downwardly therefrom which engagesmetering plate 82. Thus, rotation of the shaft 58 causes the cone 90 andmetering plate 82 to be rotated due to the pin 92 connecting the same.The pin 92 also acts as a shear pin in the metering plate 82 shouldbecome stuck. The pin 92 also permits quick and easy replacement of themetering plate 82.

A metering port or cell 94 is provided in metering plate 82 to permittablets or pellets to drop therethrough into communicating tube 96 whichextends downwardly from the metering device. An elbow 98 extendsdownwardly and laterally from the lower end of tube 96 to enable thepellets or tablets to drop into the funnel 100 which communicates withthe well 10. It can be seen that the elbow 98 permits the meteringdevice to be offset with respect to the well so that moist air risingfrom the well will not pass directly upwardly into contact with themetering device. The elbow also permits the device to be installed overthe well without the need for great accuracy in alignment.

With respect to the circuit shown in FIG. 8, the numerals 102, 104, 106and 108 refer to a pressure switch on pressure tank 15, fan motor, clockmotor and meter motor respectively which are operatively electricallyconnected to a source of 110 Volt current generally referred to by thereference numeral 110. The clock motor 106 drives the clock 112 having astop 114 thereon adapted to close the switch 116 for a predeterminedportion of its rotation as will be explained in more detail hereinafter.A clock 113 is also'provided with its operation being cumulative onclock 106 as will be explained in more detail hereinafter.

Fan motor 104 drives a fan 118 to draw air inwardly through the airinlet opening 120 formed in housing 16 and outwardly through airdischarge opening 122 formed on the opposite side of housing 16 so thatoutside air is drawn through the housing to pull the moist air outwardlytherefrom. The arrangement of the openings 120 and 122 is such that theair is drawn through and around the metering device to keep it cool andto prevent moist air from accumulating thereon.

As seen in FIG. 7, a pipe 124 extends downwardly from funnel 100. Anoptional trap door 176 is pivotally mounted in pipe 124 to selectivelyclose the same. A solenoid 128 is operatively connected to door 126 andis electrically connected to the meter motor 108 so that the door 126will only be open when the motor 108 is activated. Door 126 in itsclosed condition prevents moisture passing upwardly from the well. Anoptional trap door 130 is also provided on pipe 96 for selectivelyclosing the same at times. Door 130 is controlled by solenoid 132 whichis electrically connected to the meter motor 108 so that the door 130will only be open when the meter motor 108 is activated. Door 130 in itsclosed condition prevents moisture from moving upwardly through pipe 96.

With respect to the device illustrated in FIGS. 1-7, the normal methodof operation is as follows. The chlorine tablets or pellets 22 areinserted into the hopper through the sealed cap 24. The tablets 22 falldownwardly into the hopper as illustrated in FIG. 2 with the baffles 84and 86 preventing the tablets from becoming jammed at the lower endthereof. The ledge 124 in collar 48 prevents more than one pellet fromdropping downwardly through the port 94 into tube 96 when port 94 ispositioned over tube 96. Metering plate 82 is shown to have only oneport or cell 94 but could has as many as desired depending upon therequirements of the well. The pressure switch 102 causes the pump motor14 to be actuated when the water pressure in tank 15 drops to apredetermined level so that additional water is pumped from the wellinto the tank 15. The clock 112 is a half hour clock and runs every timethe pump motor 14 is operated. The fan motor 104 also operates each timethe pump motor operates to draw air through the housing as previouslydescribed. The meter motor 108 makes one complete revolution every 45seconds. The clock 112 is a conventional clock and closes micro-switch116 once each revolution as stop element 114 engages the switch 116. Theswitch 116 is closed for 15 seconds each time the stop element 114 comesinto engagement therewith. More than one stop element 114 could be usedif desired. With one stop element 114 in use, the switch 116 will beclosed for 15 seconds once every half-hour of operation of the pump.Fifteen seconds of energy through switch 1 16 will operate meter motor108 only one-third of a revolution.

Thus, metering plate 82 will require one and one-half hours of operationof the pump before metering port 94 will deposit a tablet into tube 96.If three ports 94 were used, they would deposit a pellet or tablet eachhalfhour of operation of the pump. If more stops 114 were utilized onthe clock 112, further combinations could be utilized.

Clock 113 operates at all times and causes a given number of tablets tobe dropped into the well if the pump is not being operated. Theoperation of clock 113 is cumulative on clock 106 so that duplicatetablets will not be dropped. The purpose of clock 113 is to deposittablets into the well even if water is not being used, as when the owneris on vacation.

It is important to note that tube 96 is not directly connected to thewell since the moisture would accumulate in the tube 96 thereby causingdifficulties in the metering device. Optional doors 126 and 130 are alsoprovided for the purpose.

The loose fitting arrangement of the teeth 72 and 74 of the clutchelements 60 and 76 respectively creates some snap action between thecomponents if the device becomes jammed. The snap action between theloosely fitting teeth tends to eliminate the jamming problem. Theassembly 66 also permits the shaft 58 to rotate without rotation of themetering plate 82 if the metering plate should become jammed since theball 68 may move out of the notch if sufficient resistance isencountered.

Thus it can be seen that an extremely unique dispensing device has beenprovided for wells which automatically deposits chemical tablets orpellets such as chlorine into the well at a rate which is directlyproportional to the amount of water being pumped from the well. Thedevice also meters tablets into the well if the pump is not being usedsuch as when the owner is on vacation or the like. The device of thisinvention accurately meters the proper amount of chemical into the wellin an efficient manner which does not require constant maintenance andattention.

A modified form of the dispensing device is illustrated in FIGS. 911 andis referred to by the reference numeral 134. Device 134 includes acylindrical housing 136 having an annular flange 138 extending outwardlytherefrom. The device is maintained on the hopper 20 by a plurality ofspring clips 140 which extend downwardly therefrom and which engage theflange 138 as seen in FIG. 9. An optional ring 142 may be provided atthe upper end of housing 136 if desired to keep the weight of thetablets or pellets in the hopper from directly bearing on the componentstherebelow.

A base plate 144 is secured to the lower end of the housing 136 by anyconvenient means such as welding or the like. A secondary base plate 146is suspended below base plate 144 by bolts 148 having collars 150mounted thereon. Motor 108 is secured to the secondary base plate 146and has a drive shaft 152 extending upwardly therefrom. A clutch element154 is secured to the shaft 152 by set screw 156 as illustrated in FIG.11. A drive pin 158 extends upwardly from clutch element 154 and isreceived by a registering hole formed in clutch element 160. Clutchelement 160 is mounted on shaft 162 which extends upwardly through baseplate 144. Clutch element 160 is provided with a bore 164 formed thereinas illustrated in FIG. 11. A rubber pin 166 is maintained in frictional.engagement with the shaft 162 by a set screw' 168 to provide clutcharrangement. Thus, under normal operation, rotation of the shaft 152will cause rotation of the clutch element 54, clutch element 160 andshaft 162 due to the frictional engagement of the inner end of therubber pin 166 and the shaft 162. If the device should become jammed,the pin 166 will slip or slide along the exterior surface of the shaft162 without causing rotation of the same.

A pipe 96 is secured to the plates 144 and 146 and extends downwardlytherefrom as illustrated in FIG. 9. The pipe 96 in FIG. 9 is identicalto the pipe 96 in FIG. 7 and has a trap door 130 provided on the lowerend thereof. A solenoid 132 is provided for opening and closing the trapdoor 130 as described in the operation of the device 16.- The onlydifference in the pipe and funnel arrangement of FIG. 9 andthat shown inFIG.

7 is that the elbow 98 has been omitted from FIG. 9.

As previously stated, shaft 162 extends upwardly through base plate 144.A metering plate 170 is secured to shaft 162 above plate 144 forrotation therewith. A plurality of metering ports or cells 172 areprovided in plate 170 and are adapted to receive one of the pellets ortablets 22 therein as will be described in more detail hereinafter. Thenumeral 174 refers to a tablet baffle means comprising a plate 176 whichrests upon stops 178 extending inwardly from housing 134 as depicted inFIG. 9. A cylindrical collar like member 180 extends downwardly fromplate 176 and has a door area 182 formed therein. Plate 176 has acentral opening 184 formed therein which communicates with the interiorof the member 182 to permit the pellets or tablets 122 to dropdownwardly therethrough to permit them to exit out through the door area182 onto the upper surface of the metering plate 170. A guide 186 isprovided on the metering plate 170 below the member 180 for guiding thetablets 122 into the cells 172.

A plurality of resilient rods 188 extend downwardly from plate 176adjacent the door area 182 with their lower ends terminating just abovethe upper surface of the metering plate 170. Likewise, a pair ofresilient rods 190 extend downwardly from plate 176 as seen in FIG. withthe lower ends thereof terminating just above the upper surface of themetering plate 170. The rods I90 serve to maintain the pellets ortablets 122 in thearea between the rods 188 and the rods 190 so that thetablets cannot pass downwardly through the pipe 96 unless a cell 172moves the same into position.

The pellets flow downwardly through the opening 184 and onto the uppersurface of the metering plate between the rods 188 and 190. Rotation ofthe metering plate 170 by the motor 108 causes the tablets to fall inone of the cells 172 as it is moved passed the door" area 182. Thetablets are dropped into the pipe 96 as the individual cell or port 172registers with the open upper end thereof.

The resilient rods 188 permit jammed tablets to pass therebeneathwithout jamming the mechanism. If the tablet was only partially receivedby the cell 172 and if the rods 188 were rigid, the engagement of thejammed tablet with the rods 188 would cause the mechanism to jam. Theresiliency of the rods 188 prevents such a ma]- function.

Thus it can be seen that both of the embodiments disclosed hereinprovide a metering device for wells or the like which will accuratelymeter chemical pellets or tablets into the well as required withoutconstant attention or maintenance. Thus it can be seen that theinvention accomplishes at least all of its stated objectives.

I claim:

1. In combination with a water well,

a chemical tablet container positioned adjacent the well opening,

a metering device in communication with said container adapted toreceive tablets therefrom and to meter tablets into said well, andcontrol means for controlling the operation of said metering device, I

said water well having a pump means associated therewith for pumpingwater from said well, said metering device being activated by saidcontrol means when said pump means is operating said container having anopen lower end, said metering device being secured to said container atthe lower end thereof and normally closing the same, said meteringdevice comprising a rotatable metering plate means having at least onetablet metering opening formed therein, a tube means on said me teringdevice for conveying metered tablets to said well, said control meanscomprising a power means for rotating said metering plate means at apredetermined rate whereby a tablet will pass downwardly through said,metering opening into said tube when said metering opening registerswith said tube,

said lower end of said container comprising a vertically disposedcylindrical collar, said device comprising a cylindrical member receivedby said collar, a base plate means secured to the lower end of saidcylindrical member, said power means comprising a meter motoroperatively secured to said base plate means and having a drive shaftextending upwardly therefrom into said cylindrical member, said meteringplate means being rotatably mounted in said cylindrical member andconnected to said drive shaft for rotation therewith, said base platemeans having an opening formed therein which registers with saidmetering opening at times, said tube means being in communication withsaid opening in said base plate means,

a slip clutch means mounted on said drive shaft means,

said drive shaft means comprising first and second shaft portions, saidfirst shaft portion being connected to said meter motor, said slipclutch means operatively interconnecting said shaft portions.

2. in combination with a water well,

a chemical tablet container positioned adjacent the well opening,

a metering device in communication with said container adapted toreceive tablets therefrom and to meter tablets into said well,

and control means for controlling the operation of said metering device,

said water well having a pump means associated therewith for pumpingwater from said well, said metering device being activated by saidcontrol means when said pump means is operating,

said metering device being powered by a meter motor, said pump meanscomprising a pressure tank means having an electrical pressure switchthereon which is operatively connected to one side of a source ofelectrical energy and which is electrically connected to said pump meansso that said pump means is actuated when the pressure in said tank meansdrops to a predetermined level, a first electrical clock meansoperatively electrically connected to said pump means whereby said clockmeans is actuated only when said pump means is actuated, a secondelectrical clock means electrically connected to said first clock meansfor actuating said first clock means, a normally open microswitch meanselectrically connected to said meter motor whereby said meter motor willonly be actuated when said micro-switch means is closed, said clockmeans having at least one actuating element thereon which is adapted toengage and close said micro-switch means for a predetermined length oftime during the operation of said clock means.

3. ln combination with a water well,

a chemical tablet container positioned adjacent the well opening,

a metering device in communication with said container adapted toreceive tablets therefrom and to meter tablets into said well,

and control means for controlling the operation of said metering device,

said water well having a pump means associated therewith for pumpingwater from said well, said metering device being activated by saidcontrol means when said pump means is operating,

said container having an open lower end, said metering device beingsecured to said container at the lower end thereof and normally closingthe same, said metering device comprising a rotatable metering platemeans having at least one tablet metering opening formed therein, a tubemeans on said metering device for conveying metered tablets to saidwell, said control means comprising a power means for rotating saidmetering plate means at a predetermined rate whereby a tablet will passdownwardly through said metering opening into said tube when saidmetering opening registers with said tube,

a first pivotal trap door being provdied on said tube means forselectively closing said tube means adjacent the lower end thereof, afirst solenoid operatively connected to said first trap door for openingand closing the same, said first solenoid means being electricallyconnected to said power means so that said first trap door will beopened when said power means is rotating said metering plate.

4. In combination with a water well,

a chemical tablet container positioned adjacent to well opening,

a metering device in communication with said container adapted toreceive tablets therefrom and to meter tablets into said well,

and control means for controlling the operation of said metering device.

said water well having a pump means associated therewith for pumpingwater from said well, said metering device being activated by saidcontrol means when said pump means is operating,

said container having an open lower end, said metering device beingsecured to said container at the lower end thereof and normally closingthe same, said metering device comprising a rotatable metering platemeans having at least one tablet metering opening formed therein, a tubemeans on said metering device for conveying metered tablets to saidwell, said control means comprising a power means for rotating saidmetering plate means at a predetermined rate whereby a tablet will passdownwardly through said metering opening into said tube when saidmetering opening registers with said tube,

said metering device having a cylindrical housing extending downwardlyfrom said container, said metering plate being positioned in saidcylindrical housing, a tablet baffle means in said cylindrical housingabove said metering plate, said tablet baffle means comprising ahorizontally disposed plate having a central opening formed therein anda cylindrical member extending downwardly therefrom, said cylindricalmember having a door area formed therein for permitting the tablets tobe deposited on a portion of the metering plate.

5. The combination of claim 1 wherein said slip clutch means comprises afirst clutch element rotatably mounted on said first shaft portion, saidfirst shaft por tion having a detent groove formed therein, a detentball normally in engagement with said detent groove, a spring meansyieldably urging said detent ball into engagement with said detentgroove, a collar element secured to said first clutch element forrotation therewith, said collar element having a bore formed therein,said spring means being positioned in said bore so that rotation of saidfirst shaft portion'will normally cause the rotation of said collarelement and said first clutch element, and a second clutch elementsecured to said second shaft portion, said second clutch element beingin mesh with said first clutch element.

6. The combination of claim I wherein said clutch elements have teethextending therefrom which loosely mesh with each other whereby apredetermined amount of play exists between said clutch elements.

7. In combination with a water well,

a chemical tablet container positioned adjacent the well opening,

a metering device in communication with said container adapted toreceive tablets therefrom and to meter tablets into said well,

control means for controlling the operation of said metering device, 1 l

said water well having a pump means associated therewith for pumpingwater from said well, said metering device being activated by saidcontrol means when said pump means is operating, said container and saidmetering device being enclosed by a housing positioned over said well,and an exhaust fan means mounted on said housing for exhausting air fromthe interior of said housing. 8. The combination of claim 6 wherein anair inlet opening is formed in said housing opposite to said exhaust fanmeans, said metering device being positioned between said air inletopening and said exhaust fan means so that air will be passed aroundsaid metering tube means, a second trap door on said second tube meansfor selectively closing the same to prevent well moisture from passingupwardly therethrough, a second solenoid means operatively connected tosaid second trap door for opening and closing the same, said secondsolenoid means being electrically connected to said power means so thatsaid second trap door will be opened when said power means is rotatingsaid metering plate.

1 1. The combination of claim 4 wherein resilient rod members aresecured to and extend downwardly from said horizontally disposed plate,the lower ends of said resilient rods terminating above the uppersurface of said metering plate, said resilient rod members yieldablymaintaining the tablets on a predetermined portion of the meteringplate.

12. The combination of claim 11 wherein a plurality of the rod membersare positioned between the door area of said tablet baffle means and theupper end of said tube.

1. In combination with a water well, a chemical tablet containerpositioned adjacent the well opening, a metering device in communicationwith said container adapted to receive tablets therefrom and to metertablets into said well, And control means for controlling the operationof said metering device, said water well having a pump means associatedtherewith for pumping water from said well, said metering device beingactivated by said control means when said pump means is operating, saidcontainer having an open lower end, said metering device being securedto said container at the lower end thereof and normally closing thesame, said metering device comprising a rotatable metering plate meanshaving at least one tablet metering opening formed therein, a tube meanson said metering device for conveying metered tablets to said well, saidcontrol means comprising a power means for rotating said metering platemeans at a predetermined rate whereby a tablet will pass downwardlythrough said metering opening into said tube when said metering openingregisters with said tube, said lower end of said container comprising avertically disposed cylindrical collar, said device comprising acylindrical member received by said collar, a base plate means securedto the lower end of said cylindrical member, said power means comprisinga meter motor operatively secured to said base plate means and having adrive shaft extending upwardly therefrom into said cylindrical member,said metering plate means being rotatably mounted in said cylindricalmember and connected to said drive shaft for rotation therewith, saidbase plate means having an opening formed therein which registers withsaid metering opening at times, said tube means being in communicationwith said opening in said base plate means, a slip clutch means mountedon said drive shaft means, said drive shaft means comprising first andsecond shaft portions, said first shaft portion being connected to saidmeter motor, said slip clutch means operatively interconnecting saidshaft portions.
 2. In combination with a water well, a chemical tabletcontainer positioned adjacent the well opening, a metering device incommunication with said container adapted to receive tablets therefromand to meter tablets into said well, and control means for controllingthe operation of said metering device, said water well having a pumpmeans associated therewith for pumping water from said well, saidmetering device being activated by said control means when said pumpmeans is operating, said metering device being powered by a meter motor,said pump means comprising a pressure tank means having an electricalpressure switch thereon which is operatively connected to one side of asource of electrical energy and which is electrically connected to saidpump means so that said pump means is actuated when the pressure in saidtank means drops to a predetermined level, a first electrical clockmeans operatively electrically connected to said pump means whereby saidclock means is actuated only when said pump means is actuated, a secondelectrical clock means electrically connected to said first clock meansfor actuating said first clock means, a normally open micro-switch meanselectrically connected to said meter motor whereby said meter motor willonly be actuated when said micro-switch means is closed, said clockmeans having at least one actuating element thereon which is adapted toengage and close said micro-switch means for a predetermined length oftime during the operation of said clock means.
 3. In combination with awater well, a chemical tablet container positioned adjacent the wellopening, a metering device in communication with said container adaptedto receive tablets therefrom and to meter tablets into said well, andcontrol means for controlling the operation of said metering device,said water well having a pump means associated therewith for pumpingwater from said well, said metering device being activated by saidcontrol means when said pump means is operating, said container havingan open lower end, said metering device being secured to said containerat the lower end thereof and normally closing the same, said meteringdevice comprising a rotatable metering plate means having at least onetablet metering opening formed therein, a tube means on said meteringdevice for conveying metered tablets to said well, said control meanscomprising a power means for rotating said metering plate means at apredetermined rate whereby a tablet will pass downwardly through saidmetering opening into said tube when said metering opening registerswith said tube, a first pivotal trap door being provided on said tubemeans for selectively closing said tube means adjacent the lower endthereof, a first solenoid operatively connected to said first trap doorfor opening and closing the same, said first solenoid means beingelectrically connected to said power means so that said first trap doorwill be opened when said power means is rotating said metering plate. 4.In combination with a water well, a chemical tablet container positionedadjacent to well opening, a metering device in communication with saidcontainer adapted to receive tablets therefrom and to meter tablets intosaid well, and control means for controlling the operation of saidmetering device. said water well having a pump means associatedtherewith for pumping water from said well, said metering device beingactivated by said control means when said pump means is operating, saidcontainer having an open lower end, said metering device being securedto said container at the lower end thereof and normally closing thesame, said metering device comprising a rotatable metering plate meanshaving at least one tablet metering opening formed therein, a tube meanson said metering device for conveying metered tablets to said well, saidcontrol means comprising a power means for rotating said metering platemeans at a predetermined rate whereby a tablet will pass downwardlythrough said metering opening into said tube when said metering openingregisters with said tube, said metering device having a cylindricalhousing extending downwardly from said container, said metering platebeing positioned in said cylindrical housing, a tablet baffle means insaid cylindrical housing above said metering plate, said tablet bafflemeans comprising a horizontally disposed plate having a central openingformed therein and a cylindrical member extending downwardly therefrom,said cylindrical member having a door area formed therein for permittingthe tablets to be deposited on a portion of the metering plate.
 5. Thecombination of claim 1 wherein said slip clutch means comprises a firstclutch element rotatably mounted on said first shaft portion, said firstshaft portion having a detent groove formed therein, a detent ballnormally in engagement with said detent groove, a spring means yieldablyurging said detent ball into engagement with said detent groove, acollar element secured to said first clutch element for rotationtherewith, said collar element having a bore formed therein, said springmeans being positioned in said bore so that rotation of said first shaftportion will normally cause the rotation of said collar element and saidfirst clutch element, and a second clutch element secured to said secondshaft portion, said second clutch element being in mesh with said firstclutch element.
 6. The combination of claim 1 wherein said clutchelements have teeth extending therefrom which loosely mesh with eachother whereby a predetermined amount of play exists between said clutchelements.
 7. In combination with a water well, a chemical tabletcontainer positioned adjacent the well opening, a metering device incommunication with said container adapted to receive tablets therefromand to meter tablets into said well, control means for controlling theoperation of said metering device, said water well having a pump meansassociated therewith for pumping water from said well, said meteringdevice being activated by said control means when said pump means isoperating, said container and said metering device being enclosed by ahousing positioned over said well, and an exhaust fan means mounted onsaid housing for exhausting air from the interior of said housing. 8.The combination of claim 6 wherein an air inlet opening is formed insaid housing opposite to said exhaust fan means, said metering devicebeing positioned between said air inlet opening and said exhaust fanmeans so that air will be passed around said metering device.
 9. Thecombination of claim 6 wherein said exhaust fan means is electricallyconnected to said central means whereby said exhaust fan means will beactuated only when said pump means is actuated.
 10. The combination ofclaim 3 wherein a second tube means communicates with the well, saidtube means being spaced from said second tube means and being adapted toconvey metered tablets to said second tube means, a second trap door onsaid second tube means for selectively closing the same to prevent wellmoisture from passing upwardly therethrough, a second solenoid meansoperatively connected to said second trap door for opening and closingthe same, said second solenoid means being electrically connected tosaid power means so that said second trap door will be opened when saidpower means is rotating said metering plate.
 11. The combination ofclaim 4 wherein resilient rod members are secured to and extenddownwardly from said horizontally disposed plate, the lower ends of saidresilient rods terminating above the upper surface of said meteringplate, said resilient rod members yieldably maintaining the tablets on apredetermined portion of the metering plate.
 12. The combination ofclaim 11 wherein a plurality of the rod members are positioned betweenthe door area of said tablet baffle means and the upper end of saidtube.